1. Field of the Invention
The field of the invention is motorcycle stereo and intercom systems between the motorcycle rider and passenger.
2. Description of the Related Art
Currently available are audio stereo systems for motorcycle riders and passengers as motorcycle accessories which provide means by which the motorcycle rider and passenger may enjoy stereo music from a carried tape or disc cassette player, radio, or conversation on a Citizens Band (CB) transceiver. These systems comprise primarily two channel amplifier systems that input into the jack receptacle of the tape or disc cassette players and radio receivers, amplifying the sound in each channel and then directing it to sets of loudspeakers, such as earphones or headsets worn by the motorcycle driver and passenger. In many cases, earphones are fitted interiorly to the protective helmet worn by the rider and passenger and so oriented that the left channel of the stereo (when present) will appear in each of the left helmet earphones of the rider and passenger, and the right stereo channel (when present) appearing in the right helmet earphones of the motorcycle rider and passenger. For monaural sounds, the same sounds appear in both channels. In these cases, electrical cords connect to the earphone of each the rider and the passenger and plug into convenient connectors or jacks of the sound system to receive the audio entertainment.
The problems come when attempts are made to interconnect the stereo system with an intercom microphone system which permits communication between the rider and passenger while traveling on the motorcycle. In most cases, the microphone is similarly attached to each helmet worn by the motorcycle rider and passenger such that it, at all times is immediately forward of, but in close proximity to the party's mouth. For such systems, inherent problems reside in the fact that wind noise and other outside noises are picked up by the microphone in addition to the words spoken and sent into the interconnected stereo and intercom system. One solution has been to activate the microphones of the intercom system by means of separate manually operated on/off switches so that they may be turned on when one of the parties wishes to speak, and then turned off at the conclusion of the conversation.
Other solutions have been to have the microphone system on all the time, yet, adjust the sensitivity of the system so that noise and other sounds below a certain level are not amplified throughout the system, and, when speaking above that noise level, the speaking voice will be amplified and placed upon the earphones of both parties. However, systems of this type always need continuous adjustment depending upon the noise level. Unfortunately, the noise level also appears to rise as a direct function of the speed of the motorcycle, thus continually requiring adjustment of the sensitivity level to eliminate the noise. That, of course, introduces additional problems, such as: If the motorcycle has been traveling at a high rate of speed when last using the intercom system and the motorcycle then slows down, the manually adjusted sensitivity control is set so high that when utilizing the intercom system, the voice may not exceed the previously set sensitivity for a relatively loud noise level and thus may not be heard.
In addition, many existing VOX systems (voice activated systems) turn off immediately at the end of the last word spoken, so that if there is a pause between the words of the speaker, the system will have already shut down. Then, when the system comes back on for the next word spoken, that word will appear chopped or missing altogether as it takes the system time to reactivate.
Further, problems with the VOX systems currently available as motorcycle accessories are exacerbated with the new style of sport-type motorcycles presently coming upon the market in that they have smaller farings and less wind protection for the driver and passenger than the touring type motorcycles, and consequently more outside and extraneous noise is present.
Thus it is obvious that there is need for a stereo audio system with VOX intercom which overcomes the problems above discussed, i.e., that will automatically compensate for increased wind and other noise so that both the rider and passenger are not constantly having to adjust the sensitivity control to compensate for varying wind and other noises. A VOX system that stays on for a period of time even after the last person has spoken until it is reasonably clear that there will be no more conversation, and then, after muting or cutting off the stereo system, brings the system back to full volume.
Substantially most of the above objectives were achieved in our prior patent issued Jun. 28, 1988 and bearing U.S. Pat. No. 4,754,486. However, in the invention of our prior patent, we permitted the monitoring of the stereo audio system while in the VOX intercom mode by reducing the audio sounds in one side of the helmet loudspeakers. Since the time of our prior invention and subsequent selling of many units of the VOX intercom system, we have substantially improved that VOX intercom system wherein the new invention presented herein takes out all of the stereo system sounds during VOX operation, improves the sensitivity of the system rejecting wind and road noises, and makes other improvements which are herewith disclosed.